JSFiddle - React, Tailwind, and code Playground

JavaScript

var json = {
    "categoryID" : 1,
    "categoryName" : "Stupid Questions",
    "questions" : [{
            "question" : {
                    "questionOptions" : [{
                            "questionOptionID" : 1,
                            "optionText" : "It's top secret."
                        }, {
                            "questionOptionID" : 2,
                            "optionText" : "Because I am big and your small. I am right and your wrong."
                        }, {
                            "questionOptionID" : 3,
                            "optionText" : "I will gladly pay you Tuesday for a hamburger today."
                        }
                    ],
                    "questionType" : "checkbox",
                    "questionText" : "Why can't we use more abstract table and column names?",
                    "summary" : "Question of the year"
                }
            }]
}
    
function myTransform(string) {
    // case-insensitive replace
    return string.replace(/question/i,'template');
}

function transformObject(source) {
    var result = {}
    for( var key in source ) {
        if( !source.hasOwnProperty(key) ) continue;
        var value = source[key];
        var newKey = myTransform(key);
        if( Object.prototype.toString.call(value) == "[object Array]" ) {
            result[newKey] = [];
            for( var i in value ) {
                if( !value.hasOwnProperty(i) ) continue;
                result[newKey][i] = transformObject(value[i]);
            }
        }
        else if( Object.prototype.toString.call(value) == "[object Object]" ) {
            result[newKey] = transformObject(value);
        }
        else {
            result[newKey] = value;
        }
    }
    return result;
}

var wow = transformObject(json);

console.log( 'before:' );
console.log( json );
console.log( 'after:' );
console.log( wow );